Added pad dummy instructions

data/languages/xtensa.sinc

@@ -122,6 +122,14 @@ define token narrowinsn(16)
 
 ;
 
+define token opbyte (8)
+	op0_8        = (0,7)
+;	
+
+define token opword (16)
+	op0_16        = (0,15)
+;
+
 attach variables [ ar as at n_ar n_as n_at ] [
     a0 a1 a2 a3 a4 a5 a6 a7 a8 a9 a10 a11 a12 a13 a14 a15
 ];

data/languages/xtensaInstructions.sinc

@@ -1306,3 +1306,11 @@ macro extract_bit(val, bit, result) {
 	#*[special_register]:4 sr = at;
 	#at = tmp;
 }
+
+:pad is op0_16=0x0 {
+}
+
+:pad is op0_8=0x0 {
+}
+
+

data/languages/xtensaTodo.sinc

@@ -116,7 +116,7 @@
 :movsp at, as is op2 = 0 & op1 = 0 & ar = 0b0001 & as & at & op0 = 0 unimpl
 
 # RETW - Windowed Return, pg. 480.
-:retw is op2 = 0 & ar = 0 & as = 0 & at = 0 & u2_18.19 = 0b10 & u2_16.17 = 0b01 & op0 = 0 {
+:retw is op2 = 0 & op1 = 0 & ar = 0 & as = 0 & u2_6.7 = 0b10 & u2_4.5 = 0b01 & op0 = 0 {
     return [a0];
 }